1. Field of the Invention
This invention relates generally to devices used in the art of fish culture, and in particular to a net or netted enclosure for confining the young of fish, especially marine fish such as yellowtails and "tai" (Pacific porgies), and for rearing them in sea waters until they grow into adults. Even more particularly, the invention deals with such a fish rearing enclosure having a mouth at its top which can be readily opened or closed.
2. Prior Art
In the art of marine fish culture by use of fish rearing enclosures of the type under consideration, one of the most serious problems is how to protect the confined fish from the attack of the so-called "red tide", which is a discoloration of the surface waters of the sea by the presence of dinoflagellates in concentrations fatal to fish and other forms of marine life. When notified of an oncoming red tide, therefore, fish cultivators must quickly close the mouths of their fish rearing enclosures, if necessary, and submerge same down to the depths of the sea where the confined fish will be free from the effects of the red tide. Upon disappearance of the red tide, the enclosures may again be lifted to the surface of the sea, and their mouths may be re-opened.
Since the fish cultivators are inevitably required to work on insecure footings on the surface of the sea, however, the closing and opening of the mouths of the fish rearing enclosures as heretofore constructed has been a highly troublesome and timecomsuming procedure. This disadvantage of the prior art is not to be overlooked since any delay in the submersion of the fish rearing enclosures may result in the death of the confined fish by suffocation.